Recent publications have demonstrated that use of what is referred to as “Phase Rectified Signal Averaging” (PRSA), also known as Heart Rate Harmony (HRH), is superior to using standard deviation of normal RR intervals (SDNN) and left ventricular ejection fraction (LVEF) for prediction of late mortality after a patient has experienced an acute myocardial infarction (AMI). Holter recordings were obtained for a training sample of patients that survived an AMI. PRSA was then used to analyze the Holter recordings of the patients, to thereby predict which patients would experience late mortality (i.e., not survive) and which patient's would not experience later mortality (i.e., survive). Without elaboration, one such publication suggested that the PRSA method may also be proposed for a variety of other applications.